* bc/portable:
Remove python 2.5'isms
Makefile: add PYTHON_PATH to GIT-BUILD-OPTIONS
t/aggregate-results: accomodate systems with small max argument list length
t/t7006: ignore return status of shell's unset builtin
t/t5150: remove space from sed script
git-request-pull.sh: remove -e switch to shell interpreter which breaks ksh
t/t5800: skip if python version is older than 2.5